<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>div盒子</title>

    <style>
       div{ height:500px;
           width:500px;
           border:1px solid;
           background-color: blanchedalmond;
           margin:0 auto

       }


    </style>
</head>
<body>
<div class="gdg">


</div>

</body>
</html>